Compound, host material, electron barrier material, composition and organic light emitting element

Abstract

The present invention is able to provide an organic light emitting element having excellent characteristics by using a compound of the general formula in the organic light emitting element. In the general formula, R1 to R4 and R8 to R19 each represent a hydrogen atom, a deuterium atom, an alkyl group or an aryl group; R5 to R7 each represent a hydrogen atom, a deuterium atom or an alkyl group; and at least one of R1 to R4 represents an alkyl group or an aryl group.

Description

Compound, host material, electron blocking material, composition and organic light-emitting device

[0001] The present invention relates to a compound useful as a host material, an electron blocking material, etc., and a composition and an organic light-emitting device using the compound.

[0002] Research and development of materials for organic light-emitting devices such as organic electroluminescent devices (organic EL devices) has been actively conducted. In particular, various attempts have been made to improve the properties of organic electroluminescent devices by developing and combining new electron transport materials, hole transport materials, light-emitting materials, host materials, etc. For example, mCBP and mCP, which have the following structures, have been widely recognized as useful host materials.

[0003] In addition to these compounds having a carbazole structure, compounds having both a carbazole structure and a dibenzofuran structure have also been proposed (see Patent Document 1).

[0004] WO2021 / 157593

[0005] However, even if a conventionally used host material is used, it may not necessarily be possible to provide a light-emitting device with excellent properties. For example, when combined with a delayed fluorescent material, even if a host material that is considered useful is used as is, it is often impossible to produce an organic light-emitting device with excellent properties. In particular, when used in an organic electroluminescence device, there is room for improvement in terms of driving voltage and device life. For this reason, the present inventors have conducted research with the aim of improving the properties of organic light-emitting devices by providing an excellent host material.

[0006] As a result of extensive research, the present inventors have found that the characteristics of an organic light-emitting device can be improved by using a compound having a specific structure. The present invention has been proposed based on this finding and specifically has the following configuration.

[0007] [1] A compound represented by the following general formula (1): [In the general formula (1), R １~R ４ and R ８ ~R １９ each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group; R ５ ~R ７ each independently represents a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group; R １ ~R ４ at least one of R is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group; １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ may be bonded to each other to form a cyclic structure.] [2] R １ ~R ４ and R ８ ~R １９ are each independently a hydrogen atom, or a deuterium atom, or an atom or group selected from the group consisting of an alkyl group and an aryl group, or a group formed by combining two or more of these. １ ~R ４ [4] The compound according to [1] or [2], wherein at least one of R is an aryl group optionally substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of them. ２ [5] The compound according to any one of [1] to [3], wherein R is a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. １４ and R １７ [6] The compound according to any one of [1] to [4], wherein at least one of R is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. １ ~R １９[7] The compound according to any one of [1] to [5], wherein the total number of benzene rings contained in R is 1 to 3. ５ ~R ７ [8] The compound according to any one of [1] to [6], wherein R is independently a hydrogen atom or a deuterium atom. １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９The compound according to any one of [1] to [7], wherein at least one pair of the following is bonded to each other to form a cyclic structure. [9] A host material comprising the compound according to any one of [1] to [8].

[10] The host material according to [9], for use together with a delayed fluorescent material.

[11] An electron-blocking material comprising the compound according to any one of [1] to [8].

[12] A composition obtained by doping the compound according to any one of [1] to [8] with a delayed fluorescent material.

[13] The composition according to

[12] , which is in the form of a film.

[14] The composition according to

[12] or

[13] , wherein the delayed fluorescent material is a compound having a cyanobenzene structure in which one cyano group is substituted on the benzene ring.

[15] The composition according to

[14] , wherein the delayed fluorescent material has two or more substituted or unsubstituted carbazolyl groups bonded to the benzene ring in addition to the cyano group.

[16] The composition according to

[12] or

[13] , wherein the delayed fluorescent material is a compound having a dicyanobenzene structure in which two cyano groups are substituted on a benzene ring.

[17] The composition according to any one of

[14] to

[16] , further comprising a fluorescent compound having a lower minimum excited singlet energy than the compound represented by general formula (1) and the delayed fluorescent material.

[18] The composition according to any one of

[12] to

[17] , further comprising a host material not represented by general formula (1).

[19] An organic light-emitting device comprising the compound according to any one of [1] to [8].

[20] An organic light-emitting device having a layer made of the composition according to

[12] .

[21] The organic light-emitting device according to

[20] , wherein the layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, boron atoms, and halogen atoms.

[22] The organic light-emitting device according to

[21] , wherein the layer consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, and oxygen atoms.

[23] The organic light-emitting device according to any one of

[19] to

[22] , which is an organic electroluminescence device.

[0008] By using the compound of the present invention, it is possible to provide an organic light-emitting device having excellent characteristics. For example, organic light-emitting devices using the compound of the present invention include organic light-emitting devices having a low driving voltage and an organic light-emitting device having a long device life.

[0009] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments or specific examples of the present invention, but the present invention is not limited to such embodiments or specific examples. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. Furthermore, there are no particular limitations on the isotopes of hydrogen atoms present in the molecules of the compounds used in the present invention.

[0010] (Compound Represented by General Formula (1)) In the present invention, a compound represented by the following general formula (1) is used.

[0011] In general formula (1), R １ ~R ４ and R ８ ~R １９ each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group. １ ~R ４ and R ８ ~R １９ are each independently a hydrogen atom, or a group formed by combining two or more atoms or groups selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group. １ ~R ４ At least one of R is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group. １ ~R ４ At least one of R is an aryl group, and the aryl group may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of them. ５ ~R ７ each independently represents a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group.

[0012] In one aspect of the present invention, R １ ~R ４At least one of R is a substituted or unsubstituted aryl group, for example, only one is a substituted or unsubstituted aryl group, and only two are substituted or unsubstituted aryl groups. １ is a substituted or unsubstituted aryl group. In a preferred embodiment of the present invention, R ２ is a substituted or unsubstituted aryl group. ３ is a substituted or unsubstituted aryl group. ４ is a substituted or unsubstituted aryl group. １ ~R ４ are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group. １ ~R ４ At least one of R is a substituted or unsubstituted alkyl group, for example, only one is a substituted or unsubstituted alkyl group, and only two are substituted or unsubstituted alkyl groups. １ is a substituted or unsubstituted alkyl group. In a preferred embodiment of the present invention, R ２ is a substituted or unsubstituted alkyl group. ３ is a substituted or unsubstituted alkyl group. ４ is a substituted or unsubstituted alkyl group. １ ~R ４ are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group.

[0013] In a preferred embodiment of the present invention, R ５ ~R ７ are each independently a hydrogen atom or a deuterium atom. ５ ~R ７ At least one of R is a substituted or unsubstituted alkyl group. ５ ~R ７ In one embodiment of the present invention, all of R ５ is a substituted or unsubstituted alkyl group.６ is a substituted or unsubstituted alkyl group. ７ is a substituted or unsubstituted alkyl group.

[0014] In a preferred embodiment of the present invention, R ８ ~R １１ are each independently a hydrogen atom or a deuterium atom. ８ ~R １１ In one embodiment of the present invention, at least one of R ８ is a substituted or unsubstituted aryl group. ９ is a substituted or unsubstituted aryl group. ８ ~R １１ In one embodiment of the present invention, at least one of R １０ is a substituted or unsubstituted alkyl group. １１ is a substituted or unsubstituted alkyl group.

[0015] In one aspect of the present invention, R １２ ~R １９ are each independently a hydrogen atom or a deuterium atom. １２ ~R １９ In one aspect of the present invention, at least one of R １２ ~R １９ In one embodiment of the present invention, at least one of R １２ ~R １９ In one embodiment of the present invention, only one of R １２ ~R １９ In one embodiment of the present invention, only two of R １２ ~R １５ Only one of and R １６ ~R １９ In one aspect of the present invention, only one of R １２ is a substituted or unsubstituted aryl group.１３ is a substituted or unsubstituted aryl group. In a preferred embodiment of the present invention, R １４ is a substituted or unsubstituted aryl group. １５ is a substituted or unsubstituted aryl group. １２ ~R １９ In one embodiment of the present invention, at least one of R １２ ~R １５ and at least one of R １６ ~R １９ In one embodiment of the present invention, at least one of R １６ is a substituted or unsubstituted alkyl group. １７ is a substituted or unsubstituted alkyl group. In a preferred embodiment of the present invention, R １８ is a substituted or unsubstituted alkyl group. １９ is a substituted or unsubstituted alkyl group. In a preferred embodiment of the present invention, R １４ is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, more preferably a substituted or unsubstituted aryl group, and for example, R １２ , R １３ , R １５ ~R １９ are each independently a hydrogen atom or a deuterium atom. In a preferred embodiment of the present invention, R １４ and R １７ are each independently a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, more preferably each independently a substituted or unsubstituted aryl group, and further, for example, R １２ , R １３ , R １５ , R １６ , R １８ , R １９ are each independently a hydrogen atom or a deuterium atom. １４ and R １７ In one aspect of the invention, R １４ and R １７ are different.

[0016] In the present invention, R １ ~R １９ The total number of benzene rings contained in R is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4, for example, 1, for example, 2, or for example, 3. １ ~R １９ The total number of substituted or unsubstituted aryl groups in R is preferably 1 to 8, more preferably 1 to 4, for example 1, for example 2, for example 3. In one preferred embodiment of the present invention, １ ~R ４ and R ８ ~R １９ are each independently a hydrogen atom, a deuterium atom, or a substituted or unsubstituted aryl group. ２ is a substituted or unsubstituted aryl group, and R １４ is a substituted or unsubstituted aryl group or a substituted or unsubstituted alkyl group, and R １７ is a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group, and R １ , R ３ ~R １３ , R １５ , R １６ , R １８ , R １９ are each independently a hydrogen atom or a deuterium atom.

[0017] R １ ~R ４ , R ８ ~R １９ When the aryl group R is substituted, it is preferably an aryl group substituted with a deuterium atom, an aryl group substituted with an alkyl group, or an aryl group substituted with an aryl group. １ ~R ４ , R ８ ~R １９The aryl group that R may take is more preferably an aryl group that may be substituted with one atom or group selected from the group consisting of deuterium atoms and aryl groups, or a group formed by combining two or more atoms or groups selected from the group consisting of deuterium atoms and aryl groups. For example, it is an aryl group that may be substituted with a deuterium atom. １ ~R １９ When the alkyl group R is substituted, it is preferably an alkyl group substituted with a deuterium atom or an alkyl group substituted with an aryl group. １ ~R １９The alkyl group may be an alkyl group optionally substituted with a deuterium atom. The "alkyl group" in this application may be linear, branched, or cyclic. Furthermore, two or more of the linear, cyclic, and branched groups may be mixed. The number of carbon atoms in the alkyl group may be, for example, 1 or more, 2 or more, or 4 or more. The number of carbon atoms may be 30 or less, 20 or less, 10 or less, 6 or less, or 4 or less. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, an n-hexyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group. In one embodiment of the present invention, the number of carbon atoms in the alkyl group is 1 to 4. In one embodiment of the present invention, the alkyl group is a methyl group. In one embodiment of the present invention, the alkyl group is an isopropyl group. In one embodiment of the present invention, the alkyl group is a tert-butyl group. When a plurality of alkyl groups are present in a molecule represented by general formula (1), the alkyl groups may be the same or different from one another. In one embodiment of the present invention, all of the alkyl groups in a molecule represented by general formula (1) are the same. The number of alkyl groups in a molecule represented by general formula (1) can be 0 or more, 1 or more, 2 or more, 4 or more, or 8 or more. The number of alkyl groups in a molecule represented by general formula (1) may be 20 or less, 10 or less, 5 or less, or 3 or less. The number of alkyl groups in a molecule represented by general formula (1) may be 0. In this application, an "alkyl group optionally substituted with a deuterium atom" means that at least one of the hydrogen atoms of the alkyl group may be substituted with a deuterium atom. All of the hydrogen atoms of the alkyl group may be substituted with deuterium atoms. For example, an optionally deuterated methyl group may include CH ３ , CDH ２ , CDs ２ H, CD ３The "optionally deuterated alkyl group" is preferably a completely non-deuterated alkyl group or an alkyl group in which all hydrogen atoms are substituted with deuterium atoms. In one aspect of the present invention, an "optionally deuterated alkyl group" is selected as a completely non-deuterated alkyl group. In one aspect of the present invention, an "optionally deuterated alkyl group" is selected as an alkyl group in which all hydrogen atoms are substituted with deuterium atoms. In one aspect of the present invention, an "optionally deuterated alkyl group" is selected as a non-deuterated methyl group [—CH ３ ], a non-deuterated ethyl group [—CH ２ CH ３ ], a non-deuterated isopropyl group [—CH(CH ３ ) ２ ], a non-deuterated tert-butyl group [—C(CH ３ ) ３ ] or a methyl group in which all hydrogen atoms are deuterated [-CD ３ In one embodiment of the present invention, the "optionally deuterated alkyl group" is a non-deuterated methyl group [—CH ３ ] or a methyl group in which all hydrogen atoms are deuterated [-CD ３ In one embodiment of the present invention, the molecule represented by general formula (1) contains at least one alkyl group in which at least one hydrogen atom is substituted with a deuterium atom.

[0018] An "aryl group" may be a monocyclic ring or a fused ring formed by condensing two or more rings. When the aryl group is a monocyclic ring, it is a phenyl group. When the aryl group is a fused ring, it is a group formed by condensing one or more rings to a phenyl group. The ring fused to the phenyl group may be any of an aromatic hydrocarbon ring, an aromatic heterocyclic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocyclic ring, or a ring formed by condensing these. An aromatic hydrocarbon ring or an aromatic heterocyclic ring is preferred. An example of an aromatic hydrocarbon ring is a benzene ring. The benzene ring may be fused with another benzene ring or may be fused with a heterocyclic ring such as a pyridine ring. The aromatic heterocyclic ring refers to an aromatic ring containing a heteroatom as a ring skeleton-constituting atom, and is preferably a 5- to 7-membered ring. For example, a 5-membered ring or a 6-membered ring may be employed. In one embodiment of the present invention, a furan ring, a thiophene ring, or a pyrrole ring may be employed as the aromatic heterocyclic ring. Specific examples of rings constituting the aryl group include a benzene ring and a naphthalene ring. Specific examples of the aryl group include a phenyl group, a naphthalen-1-yl group, and a naphthalen-2-yl group. These specific groups may be substituted. In the present application, an "aryl group optionally substituted with a deuterium atom" means that at least one of the hydrogen atoms of the aryl group may be substituted with a deuterium atom. All of the hydrogen atoms of the aryl group may be substituted with deuterium atoms. For example, an optionally deuterated phenyl group includes C ６ H ５ , C ６ H ４ D, C ６ H ３ D ２ , C ６ H ２ D ３ , C ６ HD ４ , C ６ D ５The "optionally deuterated aryl group" is preferably a completely undeuterated aryl group or an aryl group in which all hydrogen atoms are substituted with deuterium atoms. In one embodiment of the present invention, an aryl group in which all hydrogen atoms are substituted with deuterium atoms is selected as the "optionally deuterated aryl group". In one embodiment of the present invention, an "optionally deuterated aryl group" is selected as the "optionally deuterated aryl group". In one embodiment of the present invention, an "optionally deuterated aryl group" is a completely undeuterated phenyl group [-C ６ H ５ ], a non-deuterated naphthyl group [—C １０ H ７ ], a phenyl group in which all hydrogen atoms are deuterated [—C ６ D ５ ], a naphthyl group in which all hydrogen atoms are deuterated [—C １０ D ７ ].

[0019] In the following, R １ ~R ４ , R ８ ~R １９ Specific examples of aryl groups that can be used are listed below. However, the aryl groups that can be used in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, * indicates a bonding position. Also, methyl groups are omitted. Therefore, Ar2 to Ar7 represent structures substituted with methyl groups.

[0020] In addition to the above specific examples, groups in which all hydrogen atoms present in the alkyl groups that are substituents of Ar2 to Ar11 are substituted with deuterium atoms, and groups in which all hydrogen atoms present in the aryl groups that are substituted on the benzene rings directly bonded to the bonding positions * of Ar12 to Ar16 are substituted with deuterium atoms are exemplified here as Ar2(d) to Ar16(d), in that order. Also, groups in which all hydrogen atoms present in Ar1 to Ar16 are substituted with deuterium atoms are exemplified here as Ar1(D) to Ar16(D), in that order. In one aspect of the present invention, R １ ~R ４ , R ８ ~R１９ The aryl group that R can take is Ar or Ar(D). １ ~R ４ , R ８ ~R １９ The aryl groups that R can take are selected from the group consisting of Ar2 to Ar11, Ar2(d) to Ar11(d), and Ar2(D) to Ar11(D). １ ~R ４ , R ８ ~R １９ The aryl groups that R can take are selected from the group consisting of Ar12 to Ar16, Ar12(d) to Ar16(d) and Ar12(D) to Ar16(D). １ ~R ４ , R ８ ~R １９ The aryl group which can be taken by is selected from the group consisting of Ar1, Ar1(D), Ar12 to Ar16, Ar12(d) to Ar16(d) and Ar12(D) to Ar16(D).

[0021] R in general formula (1) １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ may be bonded to each other to form a cyclic structure. １ ~R １１do not bond with nearby groups to form a cyclic structure. The cyclic structure may be any of an aromatic ring, a heteroaromatic ring, an aliphatic hydrocarbon ring, and an aliphatic heterocyclic ring, or may be a condensed ring of these. An aromatic ring or a heteroaromatic ring is preferred. An example of an aromatic ring is a substituted or unsubstituted benzene ring. The heteroaromatic ring refers to a ring exhibiting aromaticity that contains a heteroatom as a ring skeleton-constituting atom, and is preferably a 5- to 7-membered ring, and for example, a 5-membered ring or a 6-membered ring can be employed. In one embodiment of the present invention, a furan ring, a thiophene ring, or a pyrrole ring can be employed as the heteroaromatic ring. An example of an aliphatic hydrocarbon ring is a cyclopentadiene ring. In a preferred embodiment of the present invention, the cyclic structure is a benzene ring, a furan ring of substituted or unsubstituted benzofuran, a thiophene ring of substituted or unsubstituted benzothiophene, or a pyrrole ring of substituted or unsubstituted indole. In a preferred embodiment of the present invention, the benzofuran, benzothiophene, and indole referred to herein may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of these. In another embodiment of the present invention, the benzofuran, benzothiophene, and indole referred to herein are unsubstituted.

[0022] In one aspect of the present invention, R １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ do not bond to each other to form a cyclic structure, and the group bonded via the nitrogen atom on the right side of general formula (1) (a group having a carbazole structure) is a substituted or unsubstituted non-fused carbazole-9-yl group. １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R１７ , R １７ and R １８ , R １８ and R １９ One or more pairs (preferably one pair) of these are bonded to each other, and the group bonded at the nitrogen atom on the right side of general formula (1) forms a benzofuro[2,3-a]carbazol-1-yl group, a benzofuro[3,2-a]carbazol-1-yl group, a benzofuro[2,3-b]carbazol-1-yl group, a benzofuro[3,2-b]carbazol-1-yl group, a benzofuro[2,3-c]carbazol-1-yl group, or a benzofuro[3,2-c]carbazol-1-yl group. These groups may be substituted, and in one embodiment of the present invention, they may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more thereof. In one embodiment of the present invention, R １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ One or more pairs (preferably one pair) of these are bonded to each other, and the group bonded via the nitrogen atom on the right side of general formula (1) forms a benzothieno[2,3-a]carbazol-1-yl group, a benzothieno[3,2-a]carbazol-1-yl group, a benzothieno[2,3-b]carbazol-1-yl group, a benzothieno[3,2-b]carbazol-1-yl group, a benzothieno[2,3-c]carbazol-1-yl group, or a benzothieno[3,2-c]carbazol-1-yl group. These groups may be substituted, and in one embodiment of the present invention, they may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more thereof.

[0023] Specific examples of groups (groups having a carbazole structure) bonded via the nitrogen atom on the right side of general formula (1) are given below. However, those that can be employed in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, * indicates the bonding position to the central benzene ring in general formula (1). Ph represents a phenyl group. Methyl groups are not shown. Therefore, for example, D2 to D6 represent structures substituted with methyl groups.

[0024] In addition to the specific examples above, groups in which all hydrogen atoms present in the alkyl and phenyl groups that are substituents of D2 to D20 and D33 to D262 are substituted with deuterium atoms are exemplified here as D263 to D511. Furthermore, groups in which all hydrogen atoms present in D1 to D262 are substituted with deuterium atoms are exemplified here as D512 to D773, in order. In one aspect of the present invention, the group (group having a carbazole structure) bonded at the nitrogen atom on the right side of general formula (1) is selected from D1 to D773. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is D1 or D512. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D1, D21 to D32, D512, and D532 to D543. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D1 to D14, D263 to D275, and D512 to D525. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D2 to D14, D263 to D275, and D513 to D525. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D1, D15 to D20, D33 to D237, D276 to D486, D512, D526 to D531, and D544 to D748. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D15 to D20, D33 to D237, D276 to D486, D526 to D531, and D544 to D748. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D1 to D20, D263 to D281, and D512 to D531. In one aspect of the present invention, the group bonded at the nitrogen atom on the right side of general formula (1) is selected from D21 to D237, D282 to D486, and D532 to D748.

[0025] Specific examples of the group having a three-ring structure on the left side of general formula (1) (substituted dibenzofuran-2-yl group) are listed below. However, what can be employed in the present invention should not be construed as being limited by the following specific examples. In the following specific examples, * indicates the bonding position to the central benzene ring in general formula (1). Methyl groups are omitted. Therefore, for example, Z13 to Z24 represent structures substituted with methyl groups.

[0026] In addition to the above specific examples, groups in which all hydrogen atoms in Z1 to Z40 are deuterated are exemplified here as Z41 to Z80, respectively. ６ H ５ ) with all hydrogen atoms deuterated ６ D ５ Examples of groups substituted with Z are Z81 to Z88, respectively. Furthermore, examples of groups in which all hydrogen atoms of the methyl group, isopropyl group, and tert-butyl group of Z17 to Z40 have been deuterated are Z89 to Z112, respectively.

[0027] In one embodiment of the present invention, the group having a three-ring structure on the left side of general formula (1) (substituted dibenzofuran-2-yl group) is selected from Z1 to Z112. In one embodiment of the present invention, the group having a three-ring structure on the left side of general formula (1) is selected from Z1 to Z28, Z41 to Z68, and Z81 to Z100.

[0028] The compound represented by general formula (1) does not contain any metal element. In one embodiment of the present invention, the compound represented by general formula (1) consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, nitrogen atoms, oxygen atoms, and sulfur atoms. In one embodiment of the present invention, the compound represented by general formula (1) consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, deuterium atoms, oxygen atoms, and nitrogen atoms. The molecular weight of the compound represented by general formula (1) is preferably 1,500 or less, more preferably 1,200 or less, and even more preferably 800 or less. For example, it may be selected within a range of 700 or less, 600 or less, or 550 or less. The lower limit of the molecular weight is the minimum molecular weight of the structure represented by general formula (1).

[0029] A preferred group of compounds represented by general formula (1) includes compounds represented by the following general formula (2): １ ~R ４ , R １２ ~R １９For the definition, explanation and preferred range of , please refer to the corresponding description of general formula (1).

[0030] A preferred group of compounds represented by general formula (1) includes compounds represented by the following general formula (3): １ , R ３ ~R １９ For the definition, explanation, and preferred range of R, please refer to the corresponding description of general formula (1). ２０ ~R ２４ R each independently represents a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group. ２０ ~R ２４ The preferred range of R in general formula (1) ８ ~R １０ You can refer to the explanation in

[0031] Specific examples of compounds represented by general formula (1) are listed below. Specific examples are shown by specifying Z and D in the general formula below in the table. Note that the compounds represented by general formula (1) that can be used in the present invention are not limited to these specific examples. In Table 1, the structures of compounds 1 to 1546, in which Z and D are groups described in each row of the table, are individually specified.

[0032]

[0033] In Table 2, the structures of compounds 1 to 86576 are specified by specifying Z and D in each structure. Each row in Table 2 sequentially specifies 773 compounds with Z fixed and D changed to D1 to D773. Compounds 1 to 1546 in Table 2 are specified as the same as compounds 1 to 1546 in Table 1.

[0034]

[0035] Compounds in which all hydrogen atoms in compounds 1 to 86576 have been replaced with deuterium atoms are exemplified herein as compounds 1(D) to 86576(D), in that order. In one embodiment of the present invention, compounds are selected from compounds 1 to 86576 and compounds 1(D) to 86576(D). In one embodiment of the present invention, compounds are selected from compounds 1 to 21644, 30921 to 52564, 61841 to 77300, 1(D) to 21644(D), 30921(D) to 52564(D), and 61841(D) to 77300(D). In one embodiment of the present invention, compounds are selected from compounds 30921 to 52564, 61841 to 77300, 1(D) to 21644(D), 30921(D) to 52564(D), and 61841(D) to 77300(D).

[0036] Examples of preferred compounds represented by formula (1) are given below.

[0037] Another preferred example of the compound group represented by general formula (1) is given below.

[0038] Another preferred example of the compound group represented by general formula (1) is given below.

[0039] The compound represented by general formula (1) is useful as a host material for doping with a light-emitting material. It is particularly useful as a host material for doping with a delayed fluorescent material. The doping material may be one or more types. The doping material is selected from those having a lower minimum excited singlet energy than the compound represented by general formula (1). The compound represented by general formula (1) is also useful as a carrier blocking material, for example, as an electron blocking material. It can be effectively used in a blocking layer (e.g., an electron blocking layer) in an organic light-emitting device such as an organic electroluminescence device.

[0040] (Delayed Fluorescent Material) The compound represented by general formula (1) is useful as a host material for use with a delayed fluorescent material. The "delayed fluorescent material" referred to here is an organic compound that undergoes reverse intersystem crossing from an excited triplet state to an excited singlet state in an excited state, and emits delayed fluorescence when returning from the excited singlet state to the ground state. In the present invention, when the emission lifetime is measured using a fluorescence lifetime measurement system (such as a streak camera system manufactured by Hamamatsu Photonics KK), a delayed fluorescent material is one in which fluorescence with an emission lifetime of 100 ns (nanoseconds) or more is observed. When a compound represented by general formula (1) is used in combination with a delayed fluorescent material, the delayed fluorescent material receives energy from the compound represented by general formula (1) in the excited singlet state and transitions to the excited singlet state. In addition, the delayed fluorescent material may receive energy from the compound represented by general formula (1) in the excited triplet state and transition to the excited triplet state. The delayed fluorescent material has a difference (ΔE ＳＴ ) is small, the delayed fluorescent material in the excited triplet state is likely to undergo reverse intersystem crossing to the delayed fluorescent material in the excited singlet state. The delayed fluorescent material in the excited singlet state generated by these pathways contributes to light emission.

[0041] The delayed fluorescent material has a difference ΔE between the lowest excited singlet energy and the lowest excited triplet energy at 77K. ＳＴ is preferably 0.3 eV or less, more preferably 0.25 eV or less, more preferably 0.2 eV or less, more preferably 0.15 eV or less, even more preferably 0.1 eV or less, even more preferably 0.07 eV or less, even more preferably 0.05 eV or less, even more preferably 0.03 eV or less, and particularly preferably 0.01 eV or less. ＳＴ If the δ is small, reverse intersystem crossing from the excited singlet state to the excited triplet state is easily achieved by absorbing thermal energy, and the material functions as a thermally activated delayed fluorescent material. Thermally activated delayed fluorescent materials absorb heat emitted by a device and relatively easily undergo reverse intersystem crossing from the excited triplet state to the excited singlet state, allowing the excited triplet energy to efficiently contribute to light emission.

[0042] In the present invention, the lowest excited singlet energy (E Ｓ１ ) and the lowest excited triplet energy (E Ｔ１ ) is a value calculated by the following procedure. ＳＴ is E Ｓ１ -E Ｔ１ (1) The lowest excited singlet energy (E Ｓ１ ) Thin film or toluene solution of the compound to be measured (concentration 10 －５ A sample is prepared by preparing a solution of 1000 mol / L. The fluorescence spectrum of this sample is measured at room temperature (300K). The fluorescence spectrum has the vertical axis representing emission and the horizontal axis representing wavelength. A tangent line is drawn to the rising edge of the short wavelength side of this emission spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis is determined. This wavelength value is converted to an energy value using the following conversion formula, and the value is called E Ｓ１ Conversion formula: E Ｓ１ [eV] = 1239.85 / λedge. The emission spectra in the examples described below were measured using an LED light source (Thorlabs, M300L4) as the excitation light source and a detector (Hamamatsu Photonics, PMA-12 multichannel spectrometer C10027-01). (2) Lowest excited triplet energy (E Ｔ１ ) lowest excited singlet energy (E Ｓ１ The same sample used in the measurement of ) is cooled to 77 [K] with liquid nitrogen, and the sample for phosphorescence measurement is irradiated with excitation light (300 nm), and the phosphorescence is measured using a detector. The emission from 100 milliseconds after irradiation with excitation light is taken as the phosphorescence spectrum. A tangent line is drawn to the rising edge on the short wavelength side of this phosphorescence spectrum, and the wavelength value λedge [nm] at the intersection of this tangent line and the horizontal axis is determined. This wavelength value is converted to an energy value using the following conversion formula, and the value E Ｔ１ Conversion formula: E Ｔ１[eV] = 1239.85 / λedge A tangent to the rising edge of the phosphorescence spectrum on the short wavelength side is drawn as follows: When moving along the spectral curve from the short wavelength side of the phosphorescence spectrum to the shortest maximum among the spectral maxima, consider a tangent at each point on the curve toward the long wavelength side. The slope of this tangent increases as the curve rises (i.e., as the vertical axis increases). The tangent drawn at the point where this slope is maximum is defined as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side. Note that maximum points having peak intensities that are 10% or less of the maximum peak intensity of the spectrum are not included in the shortest wavelength maximum, and the tangent drawn at the point where the slope is maximum and is closest to the shortest wavelength maximum is defined as the tangent to the rising edge of the phosphorescence spectrum on the short wavelength side.

[0043] In a preferred embodiment of the present invention, a compound (cyanobenzene derivative) having a cyanobenzene structure in which one cyano group is substituted on the benzene ring is used as the delayed fluorescence material. In another preferred embodiment of the present invention, a compound (dicyanobenzene derivative) having a dicyanobenzene structure in which two cyano groups are substituted on the benzene ring is used as the delayed fluorescence material. In another preferred embodiment of the present invention, a compound (azabenzene derivative) having an azabenzene structure in which at least one of the carbon atoms constituting the ring skeleton of the benzene ring is substituted with a nitrogen atom is used as the delayed fluorescence material.

[0044] In a preferred embodiment of the present invention, a compound represented by the following general formula (4) is used as the delayed fluorescent material. In general formula (4), R ２１ ~R ２３ one of R represents a cyano group or a group represented by the following general formula (5): ２１ ~R ２３ The remaining two and R ２４ and R ２５ At least one of R represents a group represented by the following general formula (6): ２１ ~R ２５ The remainder represents a hydrogen atom or a substituent (however, the substituent referred to here is not a cyano group, a group represented by the following general formula (5), or a group represented by the following general formula (6)). In general formula (5), L １ represents a single bond or a divalent linking group, R ３１ and R ３２ each independently represents a hydrogen atom or a substituent, and * represents the bonding position. In general formula (6), L ２ represents a single bond or a divalent linking group, R ３３ and R ３４ each independently represents a hydrogen atom or a substituent, and * represents the bonding position.

[0045] In a preferred embodiment of the present invention, R ２２ is a cyano group. In a preferred embodiment of the present invention, R ２２ is a group represented by general formula (5). ２１ is a cyano group or a group represented by general formula (5). ２３ is a cyano group or a group represented by general formula (5). ２１ ~R ２３ In one embodiment of the present invention, one of R ２１ ~R ２３ One of the groups is a group represented by general formula (5).

[0046] In a preferred embodiment of the present invention, L in general formula (5) １ is a single bond. In one aspect of the present invention, L １ is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group, and even more preferably a substituted or unsubstituted 1,4-phenylene group (with, for example, an alkyl group having 1 to 3 carbon atoms as the substituent). In one embodiment of the present invention, R ３１ and R ３２are each independently one group selected from the group consisting of alkyl groups (e.g., having 1 to 40 carbon atoms), aryl groups (e.g., having 6 to 30 carbon atoms), heteroaryl groups (e.g., having 5 to 30 ring skeleton atoms), alkenyl groups (e.g., having 1 to 40 carbon atoms), and alkynyl groups (e.g., having 1 to 40 carbon atoms) or a group formed by combining two or more of these groups (hereinafter, these groups are referred to as "groups of substituent group A"). In one preferred embodiment of the present invention, R ３１ and R ３２ are each independently a substituted or unsubstituted aryl group (e.g., having 6 to 30 carbon atoms), and examples of the substituent of the aryl group include the groups in Substituent Group A. In a preferred embodiment of the present invention, R ３１ and R ３２ are identical.

[0047] In a preferred embodiment of the present invention, L in general formula (6) ２ is a single bond. In one aspect of the present invention, L ２ is a divalent linking group, preferably a substituted or unsubstituted arylene group or a substituted or unsubstituted heteroarylene group, more preferably a substituted or unsubstituted arylene group, and even more preferably a substituted or unsubstituted 1,4-phenylene group (with, for example, an alkyl group having 1 to 3 carbon atoms as the substituent). In one embodiment of the present invention, R ３３ and R ３４each independently represents a substituted or unsubstituted alkyl group (e.g., having 1 to 40 carbon atoms), a substituted or unsubstituted alkenyl group (e.g., having 1 to 40 carbon atoms), a substituted or unsubstituted aryl group (e.g., having 6 to 30 carbon atoms), or a substituted or unsubstituted heteroaryl group (e.g., having 5 to 30 carbon atoms). Examples of the substituents of the alkyl group, alkenyl group, aryl group, and heteroaryl group mentioned here include a hydroxyl group, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an alkyl group (e.g., having 1 to 40 carbon atoms), an alkoxy group (e.g., having 1 to 40 carbon atoms), an alkylthio group (e.g., having 1 to 40 carbon atoms), an aryl group (e.g., having 6 to 30 carbon atoms), an aryloxy group (e.g., having 6 to 30 carbon atoms), an arylthio group (e.g., having 6 to 30 carbon atoms), a heteroaryl group (e.g., having 5 to 30 atoms constituting the ring skeleton), a heteroaryloxy group (e.g., having 5 to 30 atoms constituting the ring skeleton), and a heteroarylthio group. Examples of the substituents include one or more groups selected from the group consisting of R groups (e.g., having 5 to 30 atoms constituting the ring skeleton), acyl groups (e.g., having 1 to 40 carbon atoms), alkenyl groups (e.g., having 1 to 40 carbon atoms), alkynyl groups (e.g., having 1 to 40 carbon atoms), alkoxycarbonyl groups (e.g., having 1 to 40 carbon atoms), aryloxycarbonyl groups (e.g., having 1 to 40 carbon atoms), heteroaryloxycarbonyl groups (e.g., having 1 to 40 carbon atoms), silyl groups (e.g., trialkylsilyl groups having 1 to 40 carbon atoms), nitro groups, and cyano groups (hereinafter, these groups are referred to as "groups of substituent group B"). ３３ and R ３４ may be bonded to each other via a single bond or a linking group to form a cyclic structure. ３３ and R ３４ are aryl groups, they are preferably bonded to each other via a single bond or a linking group to form a cyclic structure. The linking group here includes —O—, —S—, —N(R ３５ ) -, -C(R ３６ ) (R ３７ )-, -C(=O)-, and -O-, -S-, -N(R ３５ ) -, -C(R ３６ ) (R ３７ )- is preferred, and —O—, —S—, —N(R ３５ )- is more preferred.３５ ~R ３７ each independently represents a hydrogen atom or a substituent. The substituent may be selected from the groups in the above-mentioned Substituent Group A or the groups in the below-mentioned Substituent Group B, and is preferably one group selected from the group consisting of alkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 14 carbon atoms, or a group formed by combining two or more of these groups.

[0048] The group represented by general formula (6) is preferably a group represented by the following general formula (7).

[0049] L in general formula (7) １１ represents a single bond or a divalent linking group. １１ For the description and preferred range of ２ The description and preferred range of R in general formula (7) can be referred to. ４１ ~R ４８ R each independently represents a hydrogen atom or a substituent. ４１ and R ４２ , R ４２ and R ４３ , R ４３ and R ４４ , R ４４ and R ４５ , R ４５ and R ４６ , R ４６ and R ４７ , R ４７ and R ４８may be bonded to each other to form a cyclic structure. The cyclic structure formed by bonding to each other may be an aromatic ring or an aliphatic ring, may contain a heteroatom, and may further be a fused ring of two or more rings. The heteroatom referred to here is preferably selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Examples of the cyclic structure formed include a benzene ring, a naphthalene ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyrrole ring, an imidazole ring, a pyrazole ring, an imidazoline ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, a cyclohexadiene ring, a cyclohexene ring, a cyclopentaene ring, a cycloheptatriene ring, a cycloheptadiene ring, a cycloheptaene ring, a furan ring, a thiophene ring, a naphthyridine ring, a quinoxaline ring, and a quinoline ring. For example, a ring formed by condensing multiple rings, such as a phenanthrene ring or a triphenylene ring, may be formed. The number of rings contained in the group represented by general formula (7) may be selected from the range of 3 to 5, or may be selected from the range of 5 to 7. ４１ ~R ４８ Examples of the substituent that R may have include the groups in the above-mentioned substituent group B, and preferably an unsubstituted alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms which may be substituted with an unsubstituted alkyl group having 1 to 10 carbon atoms. In a preferred embodiment of the present invention, R ４１ ~R ４８ is a hydrogen atom or an unsubstituted alkyl group having 1 to 10 carbon atoms. In a preferred embodiment of the present invention, R ４１ ~R ４８ is a hydrogen atom or an unsubstituted aryl group having 6 to 10 carbon atoms. ４１ ~R ４８ are all hydrogen atoms. In general formula (7), * represents a bonding position.

[0050] In a preferred embodiment of the present invention, an azabenzene derivative is used as the delayed fluorescent material. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which three of the carbon atoms constituting the ring skeleton of the benzene ring are substituted with nitrogen atoms. For example, an azabenzene derivative having a 1,3,5-triazine structure can be preferably selected. In a preferred embodiment of the present invention, the azabenzene derivative has an azabenzene structure in which two of the carbon atoms constituting the ring skeleton of the benzene ring are substituted with nitrogen atoms. For example, azabenzene derivatives having a pyridazine structure, pyrimidine structure, or pyrazine structure can be mentioned, and an azabenzene derivative having a pyrimidine structure can be preferably selected. In one embodiment of the present invention, the azabenzene derivative has a pyridine structure in which one of the carbon atoms constituting the ring skeleton of the benzene ring is substituted with a nitrogen atom.

[0051] In a preferred embodiment of the present invention, a compound represented by the following general formula (8) is used as the delayed fluorescent material. In the general formula (8), Y １ , Y ２ and Y ３ In one embodiment of the present invention, Y １ is a nitrogen atom, and Y ２ and Y ３ is a methine group. １ and Y ２ is a nitrogen atom, and Y ３ is a methine group. １ ~Y ３ In general formula (8), all of Z １ ~Z ３ Each of Z independently represents a hydrogen atom or a substituent, and at least one of them is a donor substituent. A donor substituent refers to a group having a negative Hammett σp value. １ ~Z ３ At least one of Z is a group containing a diarylamino structure (two aryl groups bonded to a nitrogen atom may be bonded to each other), more preferably a group represented by the above general formula (6), for example a group represented by the above general formula (7). １ ~Z３ In one embodiment of the present invention, only one of Z is a group represented by general formula (6) or (7). １ ~Z ３ In one embodiment of the present invention, only two of Z are independently a group represented by general formula (6) or (7). １ ~Z ３ are each independently a group represented by general formula (6) or (7). For details and preferred ranges of general formula (6) and general formula (7), reference can be made to the corresponding descriptions above. The remaining Z which are not a group represented by general formula (6) or general formula (7) １ ~Z ３ is preferably a substituted or unsubstituted aryl group (e.g., having 6 to 40 carbon atoms, preferably 6 to 20 carbon atoms), and examples of the substituent of the aryl group herein include one group selected from the group consisting of aryl groups (e.g., having 6 to 20 carbon atoms, preferably 6 to 14 carbon atoms) and alkyl groups (e.g., having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms), or a group formed by combining two or more of these. In one embodiment of the present invention, general formula (8) does not contain a cyano group.

[0052] In a preferred embodiment of the present invention, a compound represented by the following general formula (9) is used as the delayed fluorescent material. In the general formula (9), Ar 1 is the following A １ and D １ Ar forms a cyclic structure which may be substituted by Ar and represents a benzene ring, a naphthalene ring, an anthracene ring, or a phenanthrene ring. ２ , Ar ３ may each form a cyclic structure, and when a cyclic structure is formed, it represents a benzene ring, a naphthalene ring, a pyridine ring, or a benzene ring substituted with a cyano group. m1 represents an integer of 0 to 2, and m2 represents an integer of 0 to 1. A １ represents a cyano group, a phenyl group, a pyrimidyl group, a triazyl group, or a benzonitrile group. １represents a substituted or unsubstituted 5H-indolo[3,2,1-de]phenazin-5-yl group, or a substituted or unsubstituted heterocyclic fused carbazolyl group not containing a naphthalene structure, and １ When present, they may be the same or different. １ The substituents may be bonded to each other to form a ring structure. 1 is an optionally substituted phenanthrene ring, more preferably a substituted phenanthrene ring. In a preferred embodiment of the present invention, the number of substituents substituted on the phenanthrene ring is 1. In a preferred embodiment of the present invention, the number of substituents substituted on the phenanthrene ring is 2. In one embodiment of the present invention, Ar ２ , Ar ３ In a preferred embodiment of the present invention, only one of Ar ２ , Ar ３ Both form a ring structure.

[0053] Preferred compounds that can be used as delayed fluorescent materials are listed below, but the delayed fluorescent materials that can be used in the present invention are not limited to these specific examples.

[0054] In the present invention, other known delayed fluorescent materials can be used in appropriate combination with the compound represented by general formula (1). Even unknown delayed fluorescent materials can be used. Examples of delayed fluorescent materials include those described in paragraphs 0008 to 0048 and 0095 to 0133 of WO2013 / 154064, paragraphs 0007 to 0047 and 0073 to 0085 of WO2013 / 011955, paragraphs 0007 to 0033 and 0059 to 0066 of WO2013 / 081088, and paragraphs 0008 to 007 of WO2013 / 081088. 1 and 0118 to 0133, paragraphs 0009 to 0046 and 0093 to 0134 of JP 2013-256490 A, paragraphs 0008 to 0020 and 0038 to 0040 of JP 2013-116975 A, paragraphs 0007 to 0032 and 0079 to 0084 of WO 2013 / 133359 A, paragraphs 0008 to 0032 of WO 2013 / 161437 A JP-A-2014-9352, paragraphs 0007 to 0041 and 0060 to 0069, JP-A-2014-9224, paragraphs 0008 to 0048 and 0067 to 0076, JP-A-2017-119663, paragraphs 0013 to 0025, JP-A-2017-119664, paragraphs 0013 to 0026, JP-A-2017- JP-A-2017-226838, paragraphs 0010 to 0050, JP-A-2018-100411, paragraphs 0012 to 0043, and WO 2018 / 047853, paragraphs 0016 to 0044. Compounds encompassed by the general formulas described in paragraphs 0012 to 0025, particularly exemplary compounds, which emit delayed fluorescence can be mentioned.Also, Japanese Patent Application Laid-Open No. 2013-253121, WO2013 / 133359, WO2014 / 034535, WO2014 / 115743, WO2014 / 122895, WO2014 / 126200, WO2014 / 136758, WO2014 / 133121, WO2014 / 136860, WO 2014 / 196585, WO2014 / 189122, WO2014 / 168101, WO2015 / 008580, WO2014 / 203840 No. Publication, WO2015 / 002213 Publication, WO2015 / 016200 Publication, WO2015 / 019725 Publication, WO2015 / 072470 Publication, WO2015 / 1 No. 08049, WO2015 / 080182, WO2015 / 072537, WO2015 / 080183, JP2015-129240A, WO2015 / 129714, WO2015 / 129715, WO2015 / 133501, WO2015 / 136880, WO2015 / 137244 It is also possible to employ luminescent materials that emit delayed fluorescence, such as those described in WO2015 / 137202, WO2015 / 137136, WO2015 / 146541, WO2015 / 159541, pages 62 to 159 of WO2019 / 191665, and paragraphs

[0028] to

[0056] of WO2020 / 111205. The above publications described in this paragraph are incorporated herein by reference as part of this specification.

[0055] The delayed fluorescent material used in the present invention preferably does not contain metal atoms.For example, as the delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms and sulfur atoms can be selected.For example, as the delayed fluorescent material, a compound consisting of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms and oxygen atoms can be selected.For example, as the delayed fluorescent material, a compound consisting of carbon atoms, hydrogen atoms and nitrogen atoms can be selected.

[0056] (Composition) The composition of the present invention contains a compound represented by general formula (1) and a delayed fluorescent material. In one embodiment of the present invention, the composition is composed solely of one or more compounds represented by general formula (1) and one or more delayed fluorescent materials. In one embodiment of the present invention, the composition is composed solely of one compound represented by general formula (1) and one delayed fluorescent material. In one embodiment of the present invention, the composition contains a third component in addition to the compound represented by general formula (1) and the delayed fluorescent material. The third component here is neither a compound represented by general formula (1) nor a delayed fluorescent material. The third component may contain only one type, or may contain two or more types. The content of the third component in the composition may be selected from a range of 30% by weight or less, 10% by weight or less, 1% by weight or less, or 0.1% by weight or less. In one embodiment of the present invention, the third component does not emit light. In one embodiment of the present invention, the third component emits fluorescence. In a preferred embodiment of the present invention, the maximum component of light emitted from the composition of the present invention is fluorescence (including delayed fluorescence). In the composition of the present invention, the compound represented by general formula (1) is contained in a greater amount by weight than the delayed fluorescent material. The content of the compound represented by general formula (1) may be selected within a range of 3 times or more by weight of the delayed fluorescent material, 10 times or more by weight, 100 times or more by weight, 1000 times or more by weight, or, for example, 10,000 times or less by weight. In the composition of the present invention, it is preferable to select a delayed fluorescent material having an excited singlet energy lower than that of the compound represented by general formula (1). The difference in excited singlet energy may be 0.1 eV or more, 0.3 eV or more, 0.5 eV or more, or 2 eV or less, 1.5 eV or less, or 1.0 eV or less. The composition of the present invention preferably does not contain a metal element. In one aspect of the present invention, the composition of the present invention consists only of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms, and halogen atoms. In one embodiment of the present invention, the composition of the present invention consists solely of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, and oxygen atoms.

[0057] In one embodiment of the present invention, the compound represented by formula (1) is useful as a host material for use together with a delayed fluorescent material and a fluorescent compound. Therefore, in one embodiment of the present invention, the composition of the present invention includes the fluorescent compound in addition to the compound represented by formula (1) and the delayed fluorescent material.

[0058] The fluorescent compound has a lowest excited singlet energy (E Ｓ１ ) is preferably small. The fluorescent compound receives energy from the compound represented by general formula (1) and the delayed fluorescent material in an excited singlet state, and from the delayed fluorescent material that has undergone reverse intersystem crossing from an excited triplet state to an excited singlet state, transitions to a singlet excited state, and then emits fluorescence when returning to the ground state. The fluorescent compound is not particularly limited as long as it can receive energy from the compound represented by general formula (1) and the delayed fluorescent material and emit fluorescence, and the emission may be either fluorescence or delayed fluorescence. In particular, it is preferable that the light emitter used as the fluorescent compound emits fluorescence when returning from the lowest excited singlet energy level to the ground energy level. Two or more fluorescent compounds may be used. For example, by using two or more fluorescent compounds with different emission colors in combination, it is possible to emit light of a desired color. Examples of fluorescent compounds that can be used include anthracene derivatives, tetracene derivatives, naphthacene derivatives, pyrene derivatives, perylene derivatives, chrysene derivatives, rubrene derivatives, coumarin derivatives, pyran derivatives, stilbene derivatives, fluorene derivatives, anthryl derivatives, pyrromethene derivatives, terphenyl derivatives, terphenylene derivatives, fluoranthene derivatives, amine derivatives, quinacridone derivatives, oxadiazole derivatives, malononitrile derivatives, pyran derivatives, carbazole derivatives, julolidine derivatives, thiazole derivatives, derivatives containing metals (Al, Zn), and compounds having a boron-containing polycyclic aromatic skeleton such as diazaboranaphthoanthracene, and other compounds that exhibit a multiple resonance effect. These exemplary skeletons may or may not have a substituent. These exemplary skeletons may also be combined with each other.

[0059] Specific examples of fluorescent compounds include the compounds listed as specific examples of delayed fluorescent materials. In this case, the composition of the present invention contains two or more delayed fluorescent materials, with the material with a higher lowest excited singlet energy functioning as an assist dopant, and the material with a lower lowest excited singlet energy functioning as the primary emitting fluorescent compound. The compound used as the fluorescent compound preferably exhibits a PL quantum yield of 60% or more, more preferably 80% or more. Furthermore, the compound used as the fluorescent compound preferably exhibits an instantaneous fluorescence lifetime of 50 ns or less, more preferably 20 ns or less. The instantaneous fluorescence lifetime here refers to the emission lifetime of the component that decays most rapidly among multiple exponential decay components observed when measuring the emission lifetime of a compound exhibiting thermally activated delayed fluorescence. Furthermore, the compound used as the third compound preferably has a fluorescence emission rate from the lowest excited singlet (S1) to the ground state that is greater than the intersystem crossing rate from S1 to the lowest excited triplet (T1). For a method for calculating the rate constant of a compound, reference can be made to known literature on thermally activated delayed fluorescent materials (e.g., H. Uoyama, et al., Nature 492, 234 (2012) and K. Masui, et al., Org. Electron. 14, 2721, (2013)).

[0060] Preferred compounds that can be used as the fluorescent compound together with the delayed fluorescent material are listed below, but the fluorescent compounds that can be used in the present invention should not be construed as being limited to these specific examples.

[0061]

[0062] Furthermore, the compounds described in paragraphs 0220 to 0239 of WO2015 / 022974 can also be particularly preferably used as the fluorescent compound of the present invention.

[0063] In the present invention, it is also preferable to use a compound exhibiting a multiple resonance effect as a delayed fluorescent material used as an assist dopant or a fluorescent compound with a lower minimum excited singlet energy than the assist dopant. A known compound exhibiting a multiple resonance effect is 5,9-Diphenyl-5H,9H-[1,4]benzazaborino[2,3,4-kl]phenazaborine (DABNA-1), as described in Adv. Mater. 2016, 28, 2777-2781, etc. Derivatives are also known in which, by modifying DABNA-1, the energy levels of the highest accessible molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are adjusted to promote the fluorescence emission process and reverse intersystem crossing process that contribute to light emission (Angew. Chem. Int. Ed. 2018, 57, 11316-11320). Such compounds exhibiting a multiple resonance effect can also be widely employed in the present invention. As a compound that exhibits a multiple resonance effect, for example, a compound represented by the following general formula can be used.

[0064] In the general formula (10), X １ and X ２ Each independently represents O or S. １ and Y ２ are each independently a single bond, O, S or C(R ａ ) (R ｂ ) represents. １’ ~R ２２ ’ , R ａ , R ｂ each independently represents a hydrogen atom, a deuterium atom, or a substituent, and R １’ ~R ２２ ’ At least one of R is a substituent. １’ and R ２’ , R ２’ and R ３’ , R ３’ and R ４’ , R ５’ and R ６’ , R ６’ and R ７’ , R ７’ and Y １ , Y １ and R ８’ , R８’ and R ９’ , R ９’ and R １０’ , R １０’ and R １１’ , R １２’ and R １３’ , R １３’ and R １４’ , R １４’ and R １５’ , R １６’ and R １７’ , R １７’ and R １８’ , R １８’ and Y ２ , Y ２ and R １９’ , R １９’ and R ２０’ , R ２０’ and R ２１’ , R ２１’ and R ２２’ may be bonded to each other to form a cyclic structure. ２１’ and R １’ , R ４’ and R ５’ , R １０’ and R １２’ , R １５’ and R １６’ are not bonded to each other to form a cyclic structure. １’ , C-R ２’ , C-R ３’ , C-R ４’ , C-R ５’ , C-R ６’ , C-R ７’ , C-R ８’ , C-R ９’ , C-R １０’ , C-R １１’ , C-R １２’ , C-R １３’ , C-R １４’ , C-R １５’ , C-R １６’ , C-R １７’ , C-R １８’ , C-R １９’ , C-R ２０’ , C-R ２１’ , C-R ２２’may be substituted with N. Specific examples of the compound represented by general formula (10) are listed below, but the compounds represented by general formula (10) that can be used in the present invention should not be construed as being limited by the following specific examples.

[0065] In one embodiment of the present invention, the compound represented by general formula (1) can be used together with other host materials to form an emitting layer (composition) containing multiple host materials. That is, in one embodiment of the present invention, the composition of the present invention contains multiple host materials including the compound represented by general formula (1). The composition of the present invention may contain multiple types of compounds represented by general formula (1), or may use a compound represented by general formula (1) in combination with a host material not represented by general formula (1). Preferred compounds that can be used as a second host material to be used together with the compound represented by general formula (1) are listed below, but the second host material that can be used in the present invention should not be construed as being limited by these specific examples.

[0066]

[0067] The form of the composition of the present invention is not particularly limited. In a particularly preferred embodiment of the present invention, the composition of the present invention is in the form of a film. A film made of the composition of the present invention may be formed by a wet process or a dry process. In a wet process, a solution containing the composition of the present invention is applied to a surface, and after removing the solvent, an emitting layer is formed. Wet processes include, but are not limited to, spin coating, slit coating, inkjet (spray) printing, gravure printing, offset printing, and flexographic printing. In a wet process, an appropriate organic solvent capable of dissolving the composition of the present invention is selected and used. In some embodiments, a substituent (e.g., an alkyl group) that increases the solubility in organic solvents can be introduced into the compounds contained in the composition of the present invention. A vacuum deposition method is preferably used as the dry process. When using a vacuum deposition method, the compounds constituting the composition of the present invention may be co-deposited from separate deposition sources, or all compounds may be mixed and co-deposited from a single deposition source. When a single deposition source is used, a mixed powder of all compounds may be used, a compressed molded product of the mixed powder may be used, or a mixture of the compounds may be used that is heated, melted, mixed, and then cooled. In some embodiments, co-deposition can be performed under conditions where the deposition rates (weight loss rates) of multiple compounds contained in a single deposition source are identical or nearly identical, thereby forming a film having a composition ratio corresponding to the composition ratio of the multiple compounds contained in the deposition source. A film having a desired composition ratio can be easily formed by mixing multiple compounds in the same composition ratio as the composition ratio of the film to be formed and using the resulting deposition source. In some embodiments, a temperature at which the co-deposited compounds have the same weight loss rate can be specified, and this temperature can be used as the temperature during co-deposition. When forming a film by a vapor deposition method, the molecular weight of each compound constituting the composition is preferably 1500 or less, more preferably 1200 or less, even more preferably 1000 or less, and even more preferably 900 or less. The lower limit of the molecular weight may be, for example, 450, 500, or 600.

[0068] (Organic Light-Emitting Device) By forming a light-emitting layer made of the composition of the present invention, excellent organic light-emitting devices such as organic photoluminescence devices (organic PL devices) and organic electroluminescence devices (organic EL devices) can be provided. The organic light-emitting device of the present invention is a fluorescent light-emitting device, and the largest component of light emitted from the device is fluorescence (fluorescence here includes delayed fluorescence). The thickness of the light-emitting layer can be, for example, 1 to 15 nm, 2 to 10 nm, or 3 to 7 nm. Organic photoluminescence devices have a structure in which at least a light-emitting layer is formed on a substrate. Organic electroluminescence devices have a structure in which at least an anode, a cathode, and an organic layer are formed between the anode and the cathode. The organic layer includes at least a light-emitting layer, and may consist solely of the light-emitting layer, or may have one or more organic layers in addition to the light-emitting layer. Examples of such other organic layers include a hole-transport layer, a hole-injection layer, an electron-blocking layer, a hole-blocking layer, an electron-injection layer, an electron-transport layer, an exciton-blocking layer, and the like. The hole transport layer may be a hole injection transport layer having a hole injection function, and the electron transport layer may be an electron injection transport layer having an electron injection function. When the organic light-emitting element of the present invention is a multi-wavelength emitting organic light-emitting element, the shortest wavelength emission may include delayed fluorescence. Alternatively, the shortest wavelength emission may not include delayed fluorescence. When excited by thermal or electronic means, the organic light-emitting element using the composition of the present invention can emit light in the ultraviolet region, the blue, green, yellow, orange, or red region of the visible spectrum (e.g., 420 to 500 nm, 500 to 600 nm, or 600 to 700 nm), or the near-infrared region. For example, the organic light-emitting element can emit light in the red or orange region (e.g., 620 to 780 nm). For example, the organic light-emitting element can emit light in the orange or yellow region (e.g., 570 to 620 nm). For example, the organic light-emitting element can emit light in the green region (e.g., 490 to 575 nm). For example, organic light emitting devices can emit light in the blue region (eg, 400-490 nm). For example, organic light emitting devices can emit light in the ultraviolet region of the spectrum (eg, 280-400 nm).For example, organic light-emitting devices can emit light in the infrared spectral region (e.g., 780 nm to 2 μm). The largest component of the light emitted from an organic light-emitting device using the composition of the present invention is preferably light emitted from the delayed fluorescent material contained in the composition of the present invention. The light emitted from the compound represented by general formula (1) is preferably less than 10% of the light emitted from the organic light-emitting device, and may be, for example, less than 1%, less than 0.1%, less than 0.01%, or even below the detection limit. The light emitted from the delayed fluorescent material may be, for example, more than 50%, more than 90%, or more than 99% of the light emitted from the organic light-emitting device. When the layer (light-emitting layer) containing the composition of the present invention contains a fluorescent material as a third component, the largest component of the light emitted from the organic light-emitting device may be light emitted from the fluorescent material. In that case, the light emitted from the light-emitting material may be, for example, more than 50%, more than 90%, or more than 99% of the light emitted from the organic light-emitting device.

[0069] Each component of the organic electroluminescence element and each layer other than the light-emitting layer will be described below.

[0070] Substrate: In some embodiments, the organic electroluminescent device of the present invention is supported by a substrate, which is not particularly limited and may be any material commonly used in organic electroluminescent devices, such as glass, transparent plastic, quartz, and silicon.

[0071] Anode: In some embodiments, the anode of the organic electroluminescent device is made of a metal, an alloy, a conductive compound, or a combination thereof. In some embodiments, the metal, alloy, or conductive compound has a high work function (4 eV or higher). In some embodiments, the metal is Au. In some embodiments, the conductive transparent material is CuI, indium tin oxide (ITO), SnO ２ and ZnO. In some embodiments, IDIXO (In ２ O ３An amorphous material capable of forming a transparent conductive film, such as ZnO, is used. In some embodiments, the anode is a thin film. In some embodiments, the thin film is formed by evaporation or sputtering. In some embodiments, the film is patterned by a photolithography method. In some embodiments, if the pattern does not need to be highly accurate (e.g., greater than about 100 μm), the pattern may be formed using a mask with a shape suitable for evaporation or sputtering of the electrode material. In some embodiments, when a coating material such as an organic conductive compound can be applied, a wet film formation method such as a printing method or a coating method is used. In some embodiments, when emitted light passes through the anode, the anode has a transmittance of more than 10%, and the anode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the thickness of the anode is 10 to 1,000 nm. In some embodiments, the thickness of the anode is 10 to 200 nm. In some embodiments, the thickness of the anode varies depending on the material used.

[0072] Cathode: In some embodiments, the cathode is made of an electrode material such as a metal with a low work function (4 eV or less) (referred to as an electron-injecting metal), an alloy, a conductive compound, or a combination thereof. In some embodiments, the electrode material is sodium, sodium-potassium alloy, magnesium, lithium, magnesium-copper mixture, magnesium-silver mixture, magnesium-aluminum mixture, magnesium-indium mixture, aluminum-aluminum oxide (Al ２ O ３ In some embodiments, a mixture of an electron-injecting metal and a second metal is used, the second metal being a stable metal having a higher work function than the electron-injecting metal. In some embodiments, the mixture is selected from a magnesium-silver mixture, a magnesium-aluminum mixture, a magnesium-indium mixture, an aluminum-aluminum oxide (Al ２ O ３) mixture, a lithium-aluminum mixture, and aluminum. In some embodiments, the mixture improves electron injection properties and oxidation resistance. In some embodiments, the cathode is fabricated by forming an electrode material as a thin film by evaporation or sputtering. In some embodiments, the cathode has a sheet resistance of several hundred ohms per unit area or less. In some embodiments, the cathode has a thickness of 10 nm to 5 μm. In some embodiments, the cathode has a thickness of 50 to 200 nm. In some embodiments, either the anode or the cathode of the organic electroluminescent device is transparent or semitransparent to transmit emitted light. In some embodiments, a transparent or semitransparent electroluminescent device improves light radiance. In some embodiments, the cathode is formed from a conductive, transparent material as described above for the anode, thereby forming a transparent or semitransparent cathode. In some embodiments, the device includes an anode and a cathode, both of which are transparent or semitransparent.

[0073] Injection Layer: The injection layer is a layer between the electrode and the organic layer. In some embodiments, the injection layer reduces the driving voltage and enhances the light radiance. In some embodiments, the injection layer comprises a hole injection layer and an electron injection layer. The injection layer can be disposed between the anode and the emissive layer or the hole transport layer, and between the cathode and the emissive layer or the electron transport layer. In some embodiments, an injection layer is present. In some embodiments, an injection layer is not present. Below are examples of preferred compounds that can be used as hole injection materials:

[0074]

[0075] Next, preferred examples of compounds that can be used as the electron injection material will be listed.

[0076] Barrier layer: A barrier layer is a layer that can prevent charges (electrons or holes) and / or excitons present in the light-emitting layer from diffusing outside the light-emitting layer. In some embodiments, an electron blocking layer is present between the light-emitting layer and the hole transport layer and prevents electrons from passing through the light-emitting layer to the hole transport layer. In some embodiments, a hole blocking layer is present between the light-emitting layer and the electron transport layer and prevents holes from passing through the light-emitting layer to the electron transport layer. In some embodiments, a barrier layer prevents excitons from diffusing outside the light-emitting layer. In some embodiments, the electron blocking layer and the hole blocking layer constitute an exciton blocking layer. As used herein, the terms "electron blocking layer" or "exciton blocking layer" include layers that have both the functions of an electron blocking layer and an exciton blocking layer.

[0077] Hole Blocking Layer: The hole blocking layer functions as an electron transporting layer. In some embodiments, during electron transport, the hole blocking layer prevents holes from reaching the electron transporting layer. In some embodiments, the hole blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. The materials used for the hole blocking layer may be the same materials as those described above for the electron transporting layer. Examples of preferred compounds that can be used for the hole blocking layer are listed below.

[0078]

[0079] Electron Blocking Layer: The electron blocking layer transports holes. In some embodiments, during hole transport, the electron blocking layer prevents electrons from reaching the hole transport layer. In some embodiments, the electron blocking layer increases the probability of recombination of electrons and holes in the light-emitting layer. The materials used for the electron blocking layer may be the same materials as those described above for the hole transport layer. Specific examples of preferred compounds that can be used as electron blocking materials are listed below.

[0080]

[0081] Exciton Blocking Layer: The exciton blocking layer prevents excitons generated through the recombination of holes and electrons in the emissive layer from diffusing to the charge transport layer. In some embodiments, the exciton blocking layer allows for effective confinement of excitons in the emissive layer. In some embodiments, the light emission efficiency of the device is improved. In some embodiments, the exciton blocking layer is adjacent to the emissive layer on either the anode side or the cathode side, and on both sides. In some embodiments, when the exciton blocking layer is present on the anode side, it may be present between the hole transport layer and the emissive layer and adjacent to the emissive layer. In some embodiments, when the exciton blocking layer is present on the cathode side, it may be present between the emissive layer and the cathode and adjacent to the emissive layer. In some embodiments, a hole injection layer, an electron blocking layer, or a similar layer is present between the anode and the exciton blocking layer adjacent to the emissive layer on the anode side. In some embodiments, a hole injection layer, an electron blocking layer, a hole blocking layer, or a similar layer is present between the cathode and the exciton blocking layer adjacent to the emissive layer on the cathode side. In some embodiments, the exciton blocking layer comprises an excited singlet energy and an excited triplet energy, at least one of which is higher than the excited singlet energy and excited triplet energy, respectively, of the light-emitting material.

[0082] Hole Transport Layer: The hole transport layer comprises a hole transport material. In some embodiments, the hole transport layer is a single layer. In some embodiments, the hole transport layer has multiple layers. In some embodiments, the hole transport material has one of the following properties: hole injection or transport and electron blocking. In some embodiments, the hole transport material is an organic material. In some embodiments, the hole transport material is an inorganic material. Examples of known hole transport materials that can be used in the present invention include, but are not limited to, triazole derivatives, oxadiazole derivatives, imidazole derivatives, carbazole derivatives, indolocarbazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, allylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers (especially thiophene oligomers), or combinations thereof. In some embodiments, the hole transport material is selected from a porphyrin compound, an aromatic tertiary amine compound, and a styrylamine compound. In some embodiments, the hole transport material is an aromatic tertiary amine compound. Specific examples of preferred compounds that can be used as hole transport materials are listed below.

[0083]

[0084] Electron Transport Layer: The electron transport layer comprises an electron transport material. In some embodiments, the electron transport layer is a single layer. In some embodiments, the electron transport layer has multiple layers. In some embodiments, the electron transport material only needs to transport electrons injected from the cathode to the light-emitting layer. In some embodiments, the electron transport material also functions as a hole-blocking material. Examples of electron transport layers that can be used in the present invention include, but are not limited to, nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethanes, anthrone derivatives, oxadiazole derivatives, azole derivatives, azine derivatives, or combinations thereof, or polymers thereof. In some embodiments, the electron transport material is a thiadiazole derivative or a quinoxaline derivative. In some embodiments, the electron transport material is a polymer material. Specific examples of preferred compounds that can be used as electron transport materials are listed below.

[0085]

[0086] Furthermore, examples of compounds that can be added to each organic layer are given below, which may be added as a stabilizing material, for example.

[0087]

[0088] Although specific examples of preferred materials that can be used in organic electroluminescence devices have been given, the materials that can be used in the present invention should not be construed as being limited to the following exemplary compounds. Furthermore, even compounds exemplified as materials having specific functions can be diverted to be used as materials having other functions.

[0089] Devices: In some embodiments, the light-emitting layer is incorporated into a device. For example, devices include, but are not limited to, OLED bulbs, OLED lamps, television displays, computer monitors, mobile phones, and tablets. In some embodiments, the electronic device comprises an OLED having an anode, a cathode, and at least one organic layer comprising an emissive layer between the anode and the cathode. In some embodiments, the compositions described herein can be incorporated into various photosensitive or photoactivated devices, such as OLEDs or optoelectronic devices. In some embodiments, the compositions can be useful for facilitating charge or energy transfer within the device and / or as hole transport materials. Such devices include, for example, organic light-emitting diodes (OLEDs), organic integrated circuits (OICs), organic field-effect transistors (O-FETs), organic thin-film transistors (O-TFTs), organic light-emitting transistors (O-LETs), organic solar cells (O-SCs), organic optical detectors, organic photoreceptors, organic field-quenched devices (O-FQDs), light-emitting fuel cells (LECs), or organic laser diodes (O-lasers).

[0090] Bulb or Lamp: In some embodiments, an electronic device comprises an OLED comprising an anode, a cathode, and at least one organic layer comprising an emissive layer between the anode and the cathode. In some embodiments, the device comprises OLEDs of different colors. In some embodiments, the device comprises an array comprising a combination of OLEDs. In some embodiments, the combination of OLEDs is a three-color combination (e.g., RGB). In some embodiments, the combination of OLEDs is a combination of colors that are not red, green, or blue (e.g., orange and yellow-green). In some embodiments, the combination of OLEDs is a two-color, four-color, or more-color combination. In some embodiments, the device is an OLED light comprising: a circuit board having a first side with a mounting surface and an opposite second side, the circuit board defining at least one opening; at least one OLED on the mounting surface, the at least one OLED having a light-emitting configuration including an anode, a cathode, and at least one organic layer including an emissive layer between the anode and the cathode; a housing for the circuit board; and at least one connector disposed on an end of the housing, the housing and the connector defining a package suitable for attachment to a lighting fixture. In some embodiments, the OLED light has multiple OLEDs mounted on the circuit board such that light is emitted in multiple directions. In some embodiments, a portion of the light emitted in a first direction is polarized and emitted in a second direction. In some embodiments, a reflector is used to polarize the light emitted in the first direction.

[0091] Displays or Screens: In some embodiments, the light-emitting layers of the present invention can be used in screens or displays. In some embodiments, the compounds of the present invention are deposited onto a substrate using processes such as, but not limited to, vacuum evaporation, deposition, vapor deposition, or chemical vapor deposition (CVD). In some embodiments, the substrate is a photoplate structure useful for two-sided etching to provide pixels with unique aspect ratios. The screen (also called a mask) is used in the manufacturing process of OLED displays. The corresponding artwork pattern design allows for the placement of very steep, narrow tie bars between pixels in the vertical direction and large, wide, beveled openings in the horizontal direction. This allows for the fine patterning of pixels required for high-resolution displays while optimizing chemical vapor deposition on the TFT backplane. Internal pixel patterning allows for the construction of three-dimensional pixel openings with various aspect ratios in the horizontal and vertical directions. Furthermore, the use of imaged "stripes" or halftone circles in pixel regions protects etching in certain areas until these specific patterns are undercut and removed from the substrate. At that time, all pixel areas experience similar etching rates, but their depth varies depending on the halftone pattern. Varying the size and spacing of the halftone patterns allows for etching with varying degrees of protection within a pixel, enabling the deep, localized etching required to create steep vertical bevel angles. A preferred material for the deposition mask is Invar. Invar is a metal alloy cold-rolled into long, thin sheets at steel mills. Invar cannot be electrodeposited onto a spin mandrel as a nickel mask. A suitable, low-cost method for creating open areas in a deposition mask is by wet chemical etching. In some embodiments, the screen or display pattern is a pixel matrix on a substrate. In some embodiments, the screen or display pattern is fabricated using lithography (e.g., photolithography and e-beam lithography).In some embodiments, the screen or display pattern is fabricated using wet chemical etching. In further embodiments, the screen or display pattern is fabricated using plasma etching.

[0092] Device Manufacturing Method: OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Typically, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarization film to the TFT, sequentially forming a pixel electrode, an emissive layer, a counter electrode, and an encapsulation layer, and then cutting the mother panel. OLED displays are generally manufactured by forming a large mother panel and then cutting the mother panel into cell panels. Typically, each cell panel on the mother panel is formed by forming a thin film transistor (TFT) having an active layer and source / drain electrodes on a base substrate, applying a planarization film to the TFT, sequentially forming a pixel electrode, an emissive layer, a counter electrode, and an encapsulation layer, and then cutting the mother panel.

[0093] Another aspect of the present invention provides a method for manufacturing an organic light-emitting diode (OLED) display, the method including: forming a barrier layer on a base substrate of a mother panel; forming a plurality of display units on the barrier layer in cell panel units; forming an encapsulation layer on each of the display units of the cell panel; and applying an organic film to an interface between the cell panels. In some embodiments, the barrier layer is an inorganic film, for example, made of SiNx, and edges of the barrier layer are covered with an organic film made of polyimide or acrylic. In some embodiments, the organic film assists in soft cutting of the mother panel into cell panel units. In some embodiments, the thin film transistor (TFT) layer includes a light-emitting layer, a gate electrode, and source / drain electrodes. Each of the plurality of display units may include a thin film transistor (TFT) layer, a planarization film formed on the TFT layer, and a light-emitting unit formed on the planarization film, and the organic film applied to the interface is made of the same material as the planarization film and is formed simultaneously with the formation of the planarization film. In some embodiments, the light-emitting units are coupled to the TFT layer by a passivation layer, a planarization film therebetween, and an encapsulation layer that covers and protects the light-emitting units. In some embodiments of the manufacturing method, the organic film is not coupled to either the display unit or the encapsulation layer.

[0094] Each of the organic film and the planarization film may comprise one of polyimide and acrylic. In some embodiments, the barrier layer may be an inorganic film. In some embodiments, the base substrate may be formed of polyimide. The method may further include attaching a carrier substrate formed of a glass material to one surface of the base substrate formed of polyimide before forming a barrier layer on the other surface of the base substrate, and separating the carrier substrate from the base substrate before cutting along the interface. In some embodiments, the OLED display is a flexible display. In some embodiments, the passivation layer is an organic film disposed on the TFT layer to cover the TFT layer. In some embodiments, the planarization film is an organic film formed on the passivation layer. In some embodiments, the planarization film, like the organic film formed on the edge of the barrier layer, is formed of polyimide or acrylic. In some embodiments, the planarization film and the organic film are formed simultaneously during the manufacture of the OLED display. In some embodiments, the organic film may be formed on the edge of the barrier layer, such that a portion of the organic film is in direct contact with the base substrate and a remaining portion of the organic film is in contact with the barrier layer while surrounding the edge of the barrier layer.

[0095] In some embodiments, the light-emitting layer includes a pixel electrode, a counter electrode, and an organic light-emitting layer disposed between the pixel electrode and the counter electrode. In some embodiments, the pixel electrode is connected to a source / drain electrode of the TFT layer. In some embodiments, when a voltage is applied to the pixel electrode through the TFT layer, an appropriate voltage is formed between the pixel electrode and the counter electrode, causing the organic light-emitting layer to emit light, thereby forming an image. Hereinafter, an image-forming unit including a TFT layer and a light-emitting unit is referred to as a display unit. In some embodiments, an encapsulation layer that covers the display unit and prevents penetration of external moisture may be formed into a thin-film encapsulation structure in which organic films and inorganic films are alternately stacked. In some embodiments, the encapsulation layer has a thin-film encapsulation structure in which multiple thin films are stacked. In some embodiments, the organic film applied to the interface portion is disposed at a distance from each of the multiple display units. In some embodiments, the organic film is formed such that a portion of the organic film directly contacts the base substrate, and a remaining portion of the organic film contacts the barrier layer while surrounding the edge of the barrier layer.

[0096] In one embodiment, the OLED display is flexible and uses a flexible base substrate made of polyimide. In some embodiments, the base substrate is formed on a carrier substrate made of a glass material, and then the carrier substrate is separated. In some embodiments, a barrier layer is formed on the surface of the base substrate opposite the carrier substrate. In one embodiment, the barrier layer is patterned according to the size of each cell panel. For example, while the base substrate is formed on all surfaces of the mother panel, the barrier layer is formed according to the size of each cell panel, thereby forming grooves at the interfaces between the barrier layers of the cell panels. Each cell panel can be cut along the grooves.

[0097] In some embodiments, the manufacturing method further includes a step of cutting along the interface, in which a groove is formed in the barrier layer and at least a portion of the organic film is formed in the groove, so that the groove does not penetrate into the base substrate. In some embodiments, a TFT layer of each cell panel is formed, and a passivation layer, which is an inorganic film, and a planarization film, which is an organic film, are disposed on and cover the TFT layer. At the same time as the planarization film, made of, for example, polyimide or acrylic, is formed, the grooves at the interface are covered with an organic film, made of, for example, polyimide or acrylic. This prevents cracks from occurring when each cell panel is cut along the grooves at the interface by allowing the organic film to absorb any impact that occurs. That is, if all barrier layers were completely exposed without the organic film, the impact would be transmitted to the barrier layer when each cell panel is cut along the grooves at the interface, thereby increasing the risk of cracks. However, in one embodiment, the grooves at the interface between the barrier layers are covered with an organic film to absorb any impact that would otherwise be transmitted to the barrier layer, allowing each cell panel to be cut softly and preventing cracks from occurring in the barrier layer. In one embodiment, the organic film and the planarization film covering the groove of the interface portion are spaced apart from each other. For example, if the organic film and the planarization film are connected to each other as one layer, external moisture may penetrate into the display unit through the planarization film and the remaining portion of the organic film, so the organic film and the planarization film are spaced apart from each other such that the organic film is spaced apart from the display unit.

[0098] In some embodiments, the display units are formed by forming light-emitting units, and an encapsulation layer is disposed on the display units to cover the display units. Thus, after the mother panel is completely manufactured, the carrier substrate supporting the base substrate is separated from the base substrate. In some embodiments, a laser beam is irradiated onto the carrier substrate, causing the carrier substrate to separate from the base substrate due to the difference in thermal expansion coefficient between the carrier substrate and the base substrate. In some embodiments, the mother panel is cut into individual cell panels. In some embodiments, the mother panel is cut along the interfaces between the cell panels using a cutter. In some embodiments, the grooves at the interfaces along which the mother panel is cut are covered with an organic film, which absorbs impact during cutting. In some embodiments, cracks in the barrier layer can be prevented during cutting. In some embodiments, the method reduces the product defect rate and stabilizes its quality. Another aspect is an OLED display having a barrier layer formed on a base substrate, display units formed on the barrier layer, an encapsulation layer formed on the display units, and an organic film applied to edges of the barrier layer.

[0099] The features of the present invention will be explained in more detail below with reference to synthesis examples and examples. The materials, processing details, processing procedures, etc. shown below can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below. The emission characteristics were evaluated using a source meter (Keithley: 2400 series), a semiconductor parameter analyzer (Agilent Technologies: E5273A), an optical power meter measuring device (Newport: 1930C), an optical spectrometer (Ocean Optics: USB2000), a spectroradiometer (Topcon: SR-3), and a streak camera (Hamamatsu Photonics K.K.: C4334 model). In the synthesis examples below, compounds represented by general formula (1) were synthesized.

[0100] (Synthesis Example 1) Synthesis of Compound 1

[0101] 2-Bromo-8-phenyldibenzofuran (2.53 g, 7.83 mmol), 4-(9H-carbazol-9-yl)phenylboronic acid (2.7 g, 9.4 mmol), tetrakistriphenylphosphinepalladium(0) (0.9 g, 0.78 mmol), and potassium carbonate (23.5 g, 3.25 mmol) were dissolved in a mixed solution of tetrahydrofuran and water (50 / 25 ml) and stirred at 75°C for 18 hours. The reaction solution was cooled to room temperature, the solvent was removed, and the resulting solid was washed with water, chloroform was added, and the solid was dried over magnesium sulfate. The solvent was then removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform = 7:3). Further recrystallization (toluene / methanol) afforded Compound 1 (3.13 g, 82%) as a white solid. 1 H NMR (400MHz, CDCl3, δ): 8.3 (s, 1H), 8.23 ​​(s, 1H), 8.18 (s, 1H), 8.16 (s, 1H), 7.92 (d, J = 8 Hz, 2H), 7.81 (d, J= 8 Hz, 1H), 7.75-7.66 (m, 7H), 7.53-7.36 (m, 7H), 7.31 (t, J = 7 Hz, 2H). MS (ASAP): 486.29 (M+H + ). Calcd. for C 36 H 23 NO: 485.18.

[0102] (Synthesis Example 2) Synthesis of Compound 16

[0103] 2-Phenyl-8-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-dibenzofuran (2.69 g, 6.75 mmol), 9-(4-bromophenyl)-3-phenyl-9H-carbazole (2.74 g, 8.1 mmol), tetrakistriphenylphosphinepalladium(0) (0.79 g, 0.68 mmol), and potassium carbonate (2.8 g, 20.3 mmol) were dissolved in a mixture of tetrahydrofuran and water (50 / 25 ml) and stirred at 75°C for 16 hours. The reaction solution was cooled to room temperature, the solvent was removed, and the resulting solid was washed with water, chloroform was added, dried over magnesium sulfate, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform = 7:3). Further recrystallization (toluene / acetonitrile) afforded compound 16 (2 g, 53%) as a white solid. 1 H NMR (400MHz, CDCl3, δ): 8.38 (s, 1H), 8.31 (s, 1H), 8.24 (s, 1H), 8.22 (d, J = 8 Hz, 1H), 7.94 (d, J = 8 Hz, 2H), 7.82 (d, J = 8 Hz, 1H), 7.76-7.67 (m, 10H), 7.58-7.45 (m, 7H), 7.43-7.32 (m, 3H). MS (ASAP): 562.32 (M+H + ). Calcd. for C 42 H 27 NO: 561.21.

[0104] (Synthesis Example 3) Synthesis of Compound 512

[0105] Compound a was obtained as a white solid (2.26 g, 77%) in the same manner as in Synthesis Example 2, except that 9-(4-bromophenyl)-3-phenyl-9H-carbazole was replaced with 1-bromo-4-iodobenzene. 1H NMR (400MHz, CDCl3, δ): 8.19 (dd, J = 2.0 Hz, 0.8 Hz, 1H), 8.16 (dd, J = 1.6 Hz, 0.8 Hz, 1H), 7.72 (dd, J = 8.4 Hz, 2.0 Hz, 1H), 7.70-7.67 (m, MS (ASAP): 399.12 (M+H) + ). Calcd. for C 24 H 15 BrO: 398.03.

[0106]

[0107] Compound a (1.37 g, 3.44 mmol), carbazole-1,2,3,4,5,6,7,8-d8 (0.66 g, 3.78 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.31 g, 0.344 mmol), tri-tert-butylphosphonium tetrafluoroborate (0.20 g, 0.688 mmol), and sodium tert-butoxide (0.66 g, 6.88 mmol) were dissolved in toluene (35 mL) and refluxed for 15 hours. The reaction solution was cooled to room temperature, insoluble matter was filtered, and the solvent was removed. Chloroform was added to the residue, and the mixture was washed twice with water. This chloroform solution was dried over magnesium sulfate, filtered, and the solvent was removed. The resulting solid was purified by silica gel column chromatography (developing solvent: hexane:chloroform = 8:2). Further recrystallization (toluene / methanol) gave compound 512 as a white solid (1.25 g, 74%). 1H NMR (400MHz, CDCl3, δ): 8.31 (d, J = 2.0 Hz, 1H), 8.24 (d, J = 1.6 Hz, 1H), 7.92 (d, J = 8.4 Hz, 2H), 7.82 (dd, J = 8.8 Hz, 2.0 Hz, 1H), 7.76-7.67 (m, 7H), 7.53-7.48 (m, 2H), 7.42-7.37 (m, 1H). MS (ASAP): 494.37 (M+H + ). Calcd. for C 36 H 15 D8NO: 493.23.

[0108] (Example 1) Preparation of a green organic electroluminescence element with a different host material Each thin film was deposited by vacuum deposition on a glass substrate on which an anode made of indium tin oxide (ITO) with a thickness of 50 nm was formed at a vacuum degree of 5×10 －５ The layers were laminated at 100 Pa. First, HAT-CN was formed on ITO to a thickness of 10 nm, and NPD was formed thereon to a thickness of 30 nm. Next, TrisPCz was formed thereon to a thickness of 10 nm. Next, Compound 1 and TADF1 were co-deposited from different evaporation sources to form a 40 nm thick light-emitting layer. The contents of Compound 1 and TADF1 were 55% by mass and 45% by mass. SF3TRZ was formed thereon to a thickness of 10 nm, and SF3TRZ and Liq were co-deposited from different evaporation sources at 70% by mass and 30% by mass, respectively, to form a 30 nm thick layer. Furthermore, Liq was formed to a thickness of 2 nm, and then aluminum (Al) was evaporated to a thickness of 100 nm to form a cathode. Organic electroluminescence device 1 was fabricated according to the above procedure. Comparative device 1-1 was fabricated according to the same procedure, except that comparative compound 1 was used instead of compound 1. When a current was applied to the electrodes of each of the fabricated devices, green delayed fluorescence was observed. ２ The driving voltage of the device 1 of the present invention was 0.3 V lower than that of the comparative device 1-1. ２The time (LT95) until the luminescence intensity reached 95% of that at the start of driving was measured when the device was driven at 1000 Hz, and it was 1.35 times longer for the device 1 of the present invention than for the comparative device 1-1. This confirms that the use of the compound of the present invention in combination with a delayed fluorescence material reduces the driving voltage and extends the device life.

[0109] (Example 2) Preparation of blue organic electroluminescence device with changed host material Device 2-1 was prepared according to the same procedure as in Example 1, except that the light-emitting layer of Example 1 was formed to a thickness of 40 nm by co-evaporating Compound 1 and TADF85 at 70% by mass and 30% by mass from different evaporation sources. Devices 2-2 and 2-3 were prepared according to the same procedure, except that Compound 1 was replaced with Compound 16 or Compound 512, respectively. Comparative device 2-1 was prepared according to the same procedure, except that Comparative Compound 2 was replaced with Compound 1. When a current was applied to the electrodes of each of the prepared devices, blue delayed fluorescence was observed. For each device, a current of 2.0 mA / cm ２ The driving voltage was measured at a current density of 1000 kJ / s, and the difference (relative value) from the driving voltage of Comparative Device 2-1 was calculated, and the results are shown in Table 3. The results in Table 3 show that the driving voltage is also reduced when the compound of the present invention is used together with a blue delayed fluorescent material.

[0110]

[0111] (Example 3) Preparation of Red Organic Electroluminescence Device Using a Different Host Material Device 3 was prepared according to the same procedure as in Example 1, except that the emitting layer of Example 1 was formed to a thickness of 40 nm by co-evaporation of Compound 1, TADF72, and F1 at concentrations of 59.5 mass%, 40 mass%, and 0.5 mass% from different evaporation sources. Comparative Device 3-1 was prepared according to the same procedure as in Example 1, except that Comparative Compound 1 was used instead of Compound 1. When a current was applied to the electrodes of each of the prepared devices, red delayed fluorescence was observed. In addition, a current of 6.3 mA / cm ２ The driving voltage of the device 3 of the present invention was 0.3 V lower than that of the comparative device 3-1. ２The external quantum yield (EQE) of the device 3 of the present invention was measured at 1000 kJ / s, and it was found to be 10% higher than that of the comparative device 3-1. This confirms that the use of the compound of the present invention together with a delayed fluorescent material or a fluorescent material also reduces the driving voltage and improves the luminous efficiency.

[0112] (Example 4) Preparation of Another Red Organic Electroluminescence Device Using a Different Host Material Device 4-1 was prepared according to the same procedure as in Example 1, except that the emitting layer of Example 1 was formed to a thickness of 40 nm by co-evaporation of Compound 1, TADF86, and E35 from different evaporation sources at 64.7 mass%, 35 mass%, and 0.3 mass%. Device 4-2 was prepared according to the same procedure, except that Compound 512 was used instead of Compound 1. Comparative Device 4-1 was prepared according to the same procedure, except that Comparative Compound 3 was used instead of Compound 1. When a current was applied to the electrodes of each of the prepared devices, red delayed fluorescence was observed. 50.0 mA / cm ２ The time (LT95) until the luminous intensity reached 95% of that at the start of driving was measured when driven at 1000 Hz, and the ratio (relative value) to the time for Comparative Device 4-1 was calculated, and the results are shown in Table 4. The results in Table 4 show that the device life is extended even when the compound of the present invention is used together with a delayed fluorescent material or a fluorescent material.

[0113]

[0114] (Example 5) Preparation of a green organic electroluminescence element with a different electron barrier material Each thin film was deposited by vacuum deposition on a glass substrate on which an anode made of indium tin oxide (ITO) with a thickness of 50 nm was formed at a vacuum degree of 5×10 －５The layers were laminated at 100 Pa. First, HAT-CN was formed on ITO to a thickness of 10 nm, NPD was formed thereon to a thickness of 30 nm, and TrisPCz was further formed to a thickness of 10 nm. Next, Compound 1 was formed thereon to a thickness of 10 nm as an electron blocking layer. Next, H1 and TADF1 were co-deposited from different evaporation sources to form a 40 nm thick light-emitting layer. The contents of H1 and TADF1 were 55% by mass and 45% by mass, respectively. SF3TRZ was formed thereon to a thickness of 10 nm, and SF3TRZ and Liq were co-deposited from different evaporation sources at 70% by mass and 30% by mass, respectively, to form a 30 nm thick layer. Furthermore, Liq was formed to a thickness of 2 nm, and then aluminum (Al) was deposited to a thickness of 100 nm to form a cathode. By the above procedure, organic electroluminescence device 5 was fabricated. Comparative element 5-1 was prepared according to the same procedure, except that comparative compound 1 was used instead of compound 1. When a current was applied to the electrodes of each of the prepared elements, green delayed fluorescence was observed. ２ The time (LT95) until the luminous intensity reached 95% of that at the start of driving was measured when driven at 400 V, and it was 1.5 times longer for Device 5 of the present invention than for Comparative Device 5-1. This confirms that the use of the compound of the present invention as an electron blocking material extends the device life.

[0115] (Example 6) Preparation of Red Organic Electroluminescence Device Using Two Types of Hosts, a Host Material and a Second Host Material When forming the light-emitting layer, Compound 1, H2, TADF15, and E35 were co-evaporated from different evaporation sources to form a 40 nm thick layer. Organic electroluminescence device 6-1 was prepared according to the same procedure as in Example 1. At this time, the ratio of Compound 1:H2:TADF15:E35 was 44.7% by mass:20% by mass:35% by mass:0.3% by mass. Organic electroluminescence devices 6-2 and 6-3 were prepared according to the same procedure, except that Compound 16 or Compound 512 was used instead of Compound 1. Comparative device 6-1 was prepared according to the same procedure, except that Comparative Compound 1 was used instead of Compound 1. When a current was applied to the electrodes of each prepared device, red delayed fluorescence was observed. For each device, 15.4 mA / cm ２ The driving voltage was measured at a current density of 1000 kJ / s, and the difference (relative value) between the driving voltage of the comparative element 6-1 and that of the comparative element 6-2 was calculated. The results are shown in Table 5.

[0116]

[0117] As shown in Table 3, the devices 6-1 to 6-3 of the present invention exhibited lower driving voltages than the comparative device 6-1. This confirmed that the driving voltage was also lower when the compound of the present invention was used together with the second host material, the delayed fluorescent material, and the fluorescent material.

[0118] As described above, the organic electroluminescence device using the compound of the present invention exhibited a lower driving voltage, a longer device life, and a higher luminous efficiency than the devices using comparative compounds 1 to 3. This is because the structure in which the substituted dibenzofuran-2-yl group and the group having a carbazole structure are arranged at the para position of the benzene ring acts advantageously to function as a host material or an electron blocking material.

[0119]

[0120] The compound represented by general formula (1) is useful, for example, as a host material or an electron blocking material. An organic light-emitting device using the compound represented by general formula (1) has excellent properties. Therefore, the present invention has high industrial applicability.

Claims

1. A compound represented by the following general formula (1): 【Chemistry 1】 [In general formula (1), R １ R 4 to R 4 each independently represent a hydrogen atom, a deuterium atom, an aryl group which may be substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of these, or a substituted or unsubstituted alkyl group; R 8 to R 19 each independently represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted aryl group, or a substituted or unsubstituted alkyl group; R ５ ~R ７ each independently represents a hydrogen atom, a deuterium atom, or a substituted or unsubstituted alkyl group, R １ ~R ４ at least one of is an aryl group optionally substituted with one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of them, or a substituted or unsubstituted alkyl group; R １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ may be bonded to each other to form a cyclic structure.

2. R １ ~R ４ and R ８ ~R １９ The compound according to claim 1, wherein each independently represents a hydrogen atom, or one atom or group selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group, or a group formed by combining two or more of these.

3. R ２ is a substituted or unsubstituted alkyl group, or an aryl group which may be substituted with one atom or group, or a group formed by combining two or more atoms selected from the group consisting of a deuterium atom, an alkyl group, and an aryl group.

4. R １４ and R １７ The compound according to claim 1 , wherein at least one of the groups is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.

5. R １ ~R １９ The compound according to claim 1, wherein the total number of benzene rings contained in

6. R ５ ~R ７ The compound of claim 1 , wherein each independently is a hydrogen atom or a deuterium atom.

7. R １２ and R １３ , R １３ and R １４ , R １４ and R １５ , R １６ and R １７ , R １７ and R １８ , R １８ and R １９ The compound of claim 1 , wherein at least one pair of:

8. A host material comprising the compound according to any one of claims 1 to 7.

9. The host material according to claim 8 for use together with a delayed fluorescent material.

10. An electron blocking material comprising the compound according to any one of claims 1 to 7.

11. A composition in which the compound according to any one of claims 1 to 7 is doped with a delayed fluorescent material.

12. The composition of claim 11 in the form of a film.

13. The composition according to claim 11, wherein the delayed fluorescent material is a compound having a cyanobenzene structure in which one cyano group is substituted on a benzene ring.

14. The composition according to claim 13, wherein the delayed fluorescent material has two or more types of substituted or unsubstituted carbazolyl groups bonded to a benzene ring in addition to the cyano group.

15. The composition according to claim 11, wherein the delayed fluorescent material is a compound having a dicyanobenzene structure in which two cyano groups are substituted on a benzene ring.

16. The composition according to claim 11, further comprising a fluorescent compound having a lowest excited singlet energy lower than that of the compound represented by general formula (1) and the delayed fluorescent material.

17. The composition according to claim 11, further comprising a host material not represented by the general formula (1).

18. An organic light-emitting device comprising the compound according to any one of claims 1 to 7.

19. An organic light-emitting device comprising a layer made of the composition according to claim 11.

20. 20. The organic light-emitting device according to claim 19, wherein the layer consists solely of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, oxygen atoms, sulfur atoms, boron atoms, and halogen atoms.

21. 21. The organic light-emitting device according to claim 20, wherein the layer consists solely of atoms selected from the group consisting of carbon atoms, hydrogen atoms, nitrogen atoms, and oxygen atoms.

22. The organic light-emitting device according to claim 18, which is an organic electroluminescent device.

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